Unlike most vitamin D supplements that are from sheep's wool. Vegan True Non-GMO Vitamin D is made from organically cultivated Agaricus bisporus mushrooms. Our bodies manufacture vitamin D when the skin is exposed to UV radiation form sunlight, but our ability to do so decreases as we age. Insufficient amounts of sun exposure as well as aging create a risk of vitamin D deficiency. Vitamin D is important for immune function and is vital for the maintenance of healthy bones and muscle strength. Vegan True Non-GMO Vitamin D provides 250% of the recommended vitamin D Daily Value. It does not contain any animal products or animal-derived ingredients.